Process for the preparation of alkali metal salts of cyanoacetone

Abstract

Alkali metal salts of cyanoacetone are prepared by reacting an acetonitrile, an acetic acid ester and an alkali metal alkoxide without distilling off the alcohol formed during the reaction. The reaction products are obtained with high yields and high purity.

We claim: 
     
       1. The method of preparing an alkali metal salt of cyanoacetone which comprises reacting acetonitrile with an acetic acid ester containing alkanol components in which the alkyl moiety is a substituted or unsubstituted, straight-chain, branched-chain or cyclic aliphatic radical of 1 to 20 carbon atoms, in the presence of an alkali metal alcoholate in which the alcohol moiety is a substituted or unsubstituted, straight-chain, branched-chain or cyclic aliphatic radical of 1 to 20 carbon atoms at elevated temperatures, without removing the alcohol formed by the reaction. 
     
     
       2. The method of claim 1, wherein said acetic acid ester is methyl acetate or ethyl acetate. 
     
     
       3. The method of claim 2, wherein the alcohol component of said acetic acid ester comprises 1 to 6 carbon atoms. 
     
     
       4. The method of claim 1, wherein said alkali metal alcoholate is sodium methoxide, sodium ethoxide or a mixture thereof. 
     
     
       5. The method of claim 1, wherein from 1 to 12 mols of acetonitrile are reacted per mol of alkali metal alcoholate. 
     
     
       6. The method of claim 1, wherein 1.5 to 6 mols of acetonitrile are reacted per mol of alkali metal alcoholate. 
     
     
       7. The method of claim 1, wherein from 1 to 2 mols of acetic acid ester are reacted per mol of alkali metal alcoholate. 
     
     
       8. The method of claim 1, wherein from 1.5 to 1.7 mols of acetic acid ester are reacted per mol of alkali metal alcoholate. 
     
     
       9. The method of claim 1, wherein the alcohol moiety of said alkali metal alcoholate and the alcohol moiety of said acetic acid ester are identical. 
     
     
       10. The method of claim 1, wherein the reaction is carried out at a temperature of 40° to 160° C. at normal pressure or at an elevated pressure of 2 to 200 bar. 
     
     
       11. The method of claim 1, wherein the reaction is performed at an elevated temperature of 80° to 120° C. under normal pressure or an elevated pressure of 2 to 200 bar. 
     
     
       12. The method of claim 1, wherein the reaction is initiated with a mixture of acetonitrile and said acetic acid ester. 
     
     
       13. The method of claim 1, wherein the reaction is performed by adding said acetic acid ester to a suspension of said alkali metal alkoxide in acetonitrile under the reaction conditions over a period of up to 10 hours. 
     
     
       14. The method of claim 1, wherein said acetic acid ester, a suspension of said alkali metal alcoholate in acetonitrile or a mixture of acetonitrile and said acetic acid ester are introduced into the reaction mixture individually or in combination with each other under the reaction conditions in portions or continuously. 
     
     
       15. The method of claim 1, wherein the reaction is performed with a mixture of acetic acid esters containing alkanol components in which the alcohol moiety is a substituted or unsubstituted, straight-chain, branched-chain or cyclic aliphatic radical having from 1 to 20 carbon atoms and a plurality of alkali metal alcoholates, the alcohol moieties of which are not identical.